206850591809 has 2 divisors, whose sum is σ = 206850591810. Its totient is φ = 206850591808.

The previous prime is 206850591763. The next prime is 206850591877. The reversal of 206850591809 is 908195058602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107877431809 + 98973160000 = 328447^2 + 314600^2 .

It is a cyclic number.

It is not a de Polignac number, because 206850591809 - 2¹⁶ = 206850526273 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (206850191809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103425295904 + 103425295905.

It is an arithmetic number, because the mean of its divisors is an integer number (103425295905).

Almost surely, 2^206850591809 is an apocalyptic number.

It is an amenable number.

206850591809 is a deficient number, since it is larger than the sum of its proper divisors (1).

206850591809 is an equidigital number, since it uses as much as digits as its factorization.

206850591809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1555200, while the sum is 53.

The spelling of 206850591809 in words is "two hundred six billion, eight hundred fifty million, five hundred ninety-one thousand, eight hundred nine".